Comment 7 for bug 1662035

Thanks ;)
Had that on my todo list but wanted to wait for the patch to land (as it determines for which elements this parameter is actually valid).

Either way it's good that it is documented now as I only learned of this parameter by accidentally stumbling across it in the Inkscape source by using Google (I had noticed that the "boolean" parameter I added in r15483 for the Scour extension didn't line up with a "description").